Kathy Sullivan has spent her life exploring the planet. She joined NASA in 1978 and was part of the space agency's first class of female astronauts. She's a veteran of three shuttle missions and was the first US woman to conduct a space walk. But in 2020 she set an entirely new record: venturing to the bottom of the Mariana Trench, the deepest part of the world’s oceans. The feat marked the first time a woman had ever traveled that far below the ocean’s surface, and it earned her the unique title of the most vertical woman in the world. After journeying far above our planet and deep below its surface, Sullivan says the two worlds aren't so different. But no matter how far she travels from civilization, Sullivan says the impact of human life is never far from sight.